' Declare ToolBar1.
Friend WithEvents ToolBar1 As System.Windows.Forms.ToolBar

' Initialize ToolBar1 with Bold(B), Italic(I), and Underline(U) buttons.
Private Sub InitializeToolBar()
    ToolBar1 = New ToolBar

    ' Set the appearance to Flat.
    ToolBar1.Appearance = ToolBarAppearance.Flat

    ' Set the toolbar to dock at the bottom of the form.
    ToolBar1.Dock = DockStyle.Bottom

    ' Set the toolbar font to 14 points and bold.
    ToolBar1.Font = New System.Drawing.Font _
        (FontFamily.GenericSansSerif, 14, FontStyle.Bold)

    ' Declare fontstyle array with the three font styles.
    Dim fonts() As FontStyle = New FontStyle() _
        {FontStyle.Bold, FontStyle.Italic, FontStyle.Underline}
    Dim count As Integer

    ' Create a button for each value in the array, setting its text to the
    ' first letter of the style and its button's tag property.
    For count = 0 To fonts.Length - 1
        Dim fontButton As New ToolBarButton(fonts(count). _
            ToString.Substring(0, 1))
        fontButton.Style = ToolBarButtonStyle.ToggleButton
        fontButton.Tag = fonts(count)
        ToolBar1.Buttons.Add(fontButton)
    Next
    Me.Controls.Add(Me.ToolBar1)
End Sub


' Declare FontStyle object, which defaults to the Regular FontStyle.
Dim style As New FontStyle

Private Sub ToolBar1_ButtonClick(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.ToolBarButtonClickEventArgs) _
    Handles ToolBar1.ButtonClick

    ' If a button is pushed, use a bitwise Or combination 
    ' of the style variable and the button tag, to set style to 
    ' the correct FontStyle. Set the button's PartialPush property to
    ' true for a Windows XP-like appearance.
    If (e.Button.Pushed) Then
        e.Button.PartialPush = True
        style = style Or e.Button.Tag

    Else
        ' If the button was not pushed, use a bitwise XOR 
        ' combination to turn off that style 
        ' and set the PartialPush property to False.
        e.Button.PartialPush = False
        style = style Xor e.Button.Tag
    End If

    ' Set the font using the existing RichTextBox font and the new
    ' style.
    RichTextBox1.Font = New Font(RichTextBox1.Font, style)
End Sub